package demo;
class Tire{
 //轮胎类
}
class Engine{
    //发动机类
      public void turnOn(){
          System.out.println("启动");
      }
      public void turnOf(){
          System.out.println("熄火");
      }
}
class VehicleSystem{
    //车载系统类
}
//车类
public class Car {
    Tire tire=new Tire();//轮胎
    Engine engine=new Engine();//引擎
    VehicleSystem vehicleSystem=new VehicleSystem();//系统
    public void turnOn(){
        engine.turnOn();
    }
    public void turnOf(){
        engine.turnOf();
    }
}
//SUV车
class SUV extends Car{
    public int id;
    public static void main(String[] args) {
        SUV suv=new SUV();
        suv.turnOn();
        suv.turnOf();
    }
}
